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AFR's bouncing, car bucking

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Old May 21, 2010 | 03:33 PM
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Default AFR's bouncing, car bucking

When I'm cruising around 3200rpm at 70kpa the car is surging and driving me nuts. I logged it and my AFR's bounch from 15.5 to 12:1 when I'm in this range. Is this my accel enrichment I need to play with.
Old May 21, 2010 | 03:45 PM
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Well judging from the log you posted I would need to see a non-imaginary log. Please post one
Old May 21, 2010 | 03:46 PM
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Want to post up your datalog and .msq?
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Old May 21, 2010 | 04:13 PM
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Post it so I can benefit thanks.
Old May 21, 2010 | 04:16 PM
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how do I post those things
Old May 21, 2010 | 04:19 PM
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At the bottom "Manage Attachments" click it.
Old May 21, 2010 | 04:22 PM
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the bouncing is around record 2100
Attached Files
File Type: xls
log8.xls (770.8 KB, 116 views)
File Type: msq
Miata Turbo 5-20.msq (35.1 KB, 118 views)
Old May 21, 2010 | 04:47 PM
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When you play the log where it's bouncing around, you can see your accel enrich is rapidly switching on and off, which is a consequence of running MAPdot based accel when your MAP signal has Tourette Syndrome. Where is your vac line to the MS sourced? If it's not already teed off the fuel pressure regulator, try that first and see if it helps.
Old May 21, 2010 | 04:51 PM
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It is sourced right where they say on the TB.
Old May 21, 2010 | 05:14 PM
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"on the TB" ≠ "teed off the FPR"

If you take the signal close to the throttle plate it will be jumpy.
Old May 21, 2010 | 05:45 PM
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what about the port at the very back of the intake manifold. I can run a reducer off that port.
Old May 21, 2010 | 10:24 PM
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"on the TB" ≠ "teed off the FPR"
"the port at the very back of the intake manifold ≠ "teed off the FPR"

tee it off the FPR, it should help in dapening the MAP signal so it will not spike and throw it into trying to add extra fuel
Old May 31, 2010 | 02:01 PM
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I believe I have the problem fixed now. Tee'd of the FPR helped but did'nt completely cure it. After some reading I put a fuel filter in the map line and know the car seems much smoother and I can't reproduce the problem. Gonna record some logs and see if my map readings look smoother as well.
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